Improvement in tools for opening and shaping the ends of glass bulbs



0. P; JAOKSON-& T. J. MGTIGHE. T001 for Opening and Shaping the Ends of Glass-Bulbs No. 222,789. Patented De c. 23,1379.

:jmvENToRs AQRN EYS LITHOGRAFHER, WASHINGTON D C UNITED PATENT OFFIGEL OLIVER 1?. JACKSON AND THOMAS J. MGTIGHE, OF PITTSBURG, PENN SYL- VANIA, ASSIGNORS, BY MESNE ASSIGNMENTS, TO WM. I. MILLER AND JOHN M.. PATTERSON, OF SAME PLACE.

IMPROVEMENT IN TOOLS FOR OPENING AND SHAPING THE ENDS OF GLASS BULBS.

Specification forming part of Letters Patent No. 222,789, dated December 23, 1879; application filed May 12, 1879.

To all whom it may concern:

Be it known that we, OLIVER 1?. JACKSON and THOMAS J MOTIGHE, of Pittsburg, in the countyof Allegheny and StateofPennsylvauia, have invented certain new and useful Improvements in Tools for Opening and Shaping the Ends of Glass Bulbs; and we do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it pertains to make and use it, reference being had to the accompanying drawings, which form part of this specification, in which- Figure 1 is a side elevation of our apparatus. Figs. 2 and 3 show the bulb at two stages of operation. Fig. 4 shows amodification. Fig. 5 shows difierent forms made in the practice of our invention.

This invention relates to a novel mode of shaping glass bulbs or spheres, and apparatus therefor, which mode consists in first making a small opening in the end of the bulb, then inserting a tool composed of two or more expansible and divergent parts, said tool being given motion in a circular direction with reference to the axis of the bulb, whereby the bulb is worked out to a cylindrical or other shape from the interior, thus drawing out the glass to a smooth and uniform diameter without causing it to thicken or buckle or become corded, as is liable to happen when the article is formed in any other manner.

The invention consists in the construction and combination of devices to the above end, all substantially as hereinafter fully described and claimed.

Th glass, being gathered on the pontil, is bl into a bulb, and then, by the proper manipulation, is made to approximate t th I shape of the article wanted. In thi 11; i a lamp-chimney, the bulb being elongated somewhat. After being brought to this shape the operator draws out the end slightly, runs a crease in it, and breaks it off, thus giving it the form as shown by A, Fig. 1, having a small hole in the end of the bulb. It is then reheat- I ed and manipulated by our process, which is as follows:

On a suitable frame, B, is a bearin g, C, carrying a shaft, D, which is given motion in a circular direction by a pulley, a, operated by a belt or cord; or any other circular motion may be imparted by suitable means. On shaft 1) are fixed two heads, E and F, having slots, in which slide the tools G, which are caused to move by the arms Z, pivoted at one end 00 he said tools and at the other to a sliding collar, 0, 011 the shaft. By means of the rod H, whose upturned end embraces collar 0, the collar may be drawn forward by a direct pull, or can be attached to a treadle or knee-lever, so as to be drawn by a push. It is caused to recover itself by a spring, 8, as soon as the pressure is released. This forward motion of the collar causes the tools G to slide past each other to the position shown in Fig. 1 by dotted lines. We prefer to make the outer ends of these tools parallel, for the purpose of better finish and truer centering. The normal position is shown by full lines. The slightly-opened and reheated bulb is presented to the tools as shown, being centered by the pontil resting on suitable guides, which being well understood by those skilled in the art need not be further explained. In this position the rod His operated, thus, by means of collar 0 and armsb, causing the tools G to advance inside the bulb and occupy the divergent positions shown by broken lines. Then, while the tools are rapidly rotated or oscillated, the pontil and its bulb are steadily withdrawn. The tools G operate against the inside face of the bulb, first giving it the conical end shown by Fig. 2, and then causing it gradually to open out to the finished form shown by Fig. 3.

The action closely imitates the formation by blowing, since the force is applied to expand the glass from within outwardly, and there fore there is no tendency ofthe glass to thicken up, buckle, or cord, as is the case when a bulb is opened by thrusting a plug or other tool into it and spreading the mouth as the tool advances into it. Likewise, the soft glass is more accurately centered, and the end formed in the foregoing manner will be axially true and its lower edge straight.

By a suitable modification in the form of the tools G the form of chimney known as hingechimneys may be made complete. A projection, m, on the tools, having a curved face, as shown, operates admirably. The eXpaudin g and diverging portions open and form the bulb to the required conical contour, and the projections m act as a stop to prevent the bulb from going too far while forming upon it the desired outwardly-turned lip, as shown by Fig. 4. We thus succeed in forming the base of three different styles of chimney, as shown by Fig. 5.

The great advantages gained by the practice of our invention are due to the peculiar manner of working the g1ass-i. (5., from with-' in outwardly, instead of, as ordinarily done, from Without inwardly. From this manner of working arise the advantages of an unimpeded expansion of the glass, giving it a smooth and uniform surface, even on the outside, a true centering of the opening with reference to the axis of the bulb, and freedom from all tendency to buckle or thicken.

The invention is applicable -to many forms of glassware other than 'lampehimneys, which need not be set forth, as they will suggest themselves to skilled minds.

We claim as our invention 1. In a machine for shaping glass bulbs, a rotary or oscillatory tool comprising two or more converging parts adapted to be inserted into the bulb and then caused to intersectingly diverge to the diameter of opening required, substantially as set forth.

2. The combination of shaft D, heads E F, intersecting sliding tools G, arms b, spring 8, and collar a, substantially as described.

In testimony that we claim the foregoing we have hereunto set our hands this 7th day of May, 1879.

OLIVER I. JACKSON. THOMAS J. MOTIGHE.

Witnesses:

A. V. D. WATTERSON, T. A. UoNNoLLY. 

